Dielectric rod leaky-wave antennas for millimeter-wave applications

Dielectric rod leaky-wave antennas have the property of being frequency scannable. Bounds are derived for the proper range of spacing of perturbations along the rod to avoid an intrusion upon a grating lobe when frequency scanning. In addition some experimental results are reported on sidelobe levels and polarizations in the far field for these antennas made from a material with
\epsilon_{r}= 2.33
at 81.5 GHz.